Fear and Public Perception

He's talking about the role fear plays in the perception of nuclear power. It's a lot of the sorts of things I say, but particularly interesting is this bit on familiarity and how it reduces fear:

You see, we sited these plants away from metropolitan areas to "protect the public" from the dangers of nuclear power. What we did when we did that was move the plants away from the people, so they became unfamiliar. The major health effect, adverse health effect of nuclear power is not radiation. It's fear. And by siting them away from the people, we insured that that would be maximized. If we're serious about health in relationship to nuclear power, we would put them in downtown, big cities, so people would see them all the time. That is really important, in terms of reducing the fear. Familiarity is the way fear is reduced. No question. It's not done intellectually. It's not done by reading a book. It's done by being there and seeing it and talking to the people who work there.

So, among other reasons, terrorism is scary because it's so rare. When it's more common -- England during the Troubles, Israel today -- people have a more rational reaction to it.

So... Could the permanently elevated terrorism danger level [1] be seen as a measure to make people used to terrorism (in a "virtual" way since actuall terrorism is so rare) and thereby to reduce fear?

A perfect illustration of this fellow's point. The recent leak at TMI exposed one worker to 16 millirem, less than the equivalent of three chest x-rays. That was the worst exposure of the entire accident. If every bit of the leak had escaped into downtown Manhattan, no health effects would have been seen in the population. And of course nothing escaped the plant at all, so it wouldn't matter where it was. But you've been so brainwashed by the popular fiction that "Nuclear = Incredibly Dangerous" that you're unable to think rationally about the dangers.

"But you've been so brainwashed by the popular fiction that "Nuclear = Incredibly Dangerous" that you're unable to think rationally about the dangers."

Hmmm it is incredibly dangerous of that there is little doubt. In Russia there is a modern "ghost town" where people cannot go. And under many tones of concreate the still smoldering heart of a power station, which when it "burnt" carried measurable amounts of radiation all across Europe.

The fact that it has only happened once does not mean it is not incredibly dangerous.

Yes, familiarity is a factor in risk perception but there are other factors. For example control is another factor. Driving is a risk we don't think about too much of the time because we are familiar with the activity and we have control--at least if the driver does. I have noticed that some people--especially spouses--tend to freak out in the passenger seat! So putting nuclear plants in urban areas won't necessarily change the perception if what you see is a heavily secured facility that controlled by others.

There's a huge well-established sociological literature on risk perception that been around for ages. If you read through some of the literature you could probably come up with ten or more factors and a bunch of models and examples.

Is this, I wonder, part of the reason people have become more afraid of crime as crime rates have gone down? And that people fear attacks from strangers more than from people they know, even in categories where the latter are far more often the perpetrators?

How do you think cities respond to accidents at the many incredibly dangerous industrial plants they contain? Your question shows that you somehow think that nuclear power is far more dangerous than anything else. It's not.

As for the danger of radiation, of course it's dangerous. Just like driving a car is dangerous, living downwind of a coal power plant is dangerous, and eating crackers is dangerous. The question is how dangerous it is. 16 millirems is not dangerous. A "major leak" would probably kill nobody, and would almost certainly kill fewer people than die from more normal pollution every day in a major city.

@Clive Robinson

The disastrous RBMK reactor design is what allowed Chernobyl to happen. This design is not used in power reactors built by any sane country. There have been countless non-nuclear accidents which killed more people than Chernobyl. And yet does anyone propose to keep ammonium nitrate cargo ships out of ports in major cities? If I say, "I want to build a nuclear power plant next to Battery Park", people will freak out. If I say, "I want to park a ship filled with ten thousand tons of fertilizer next to Battery Park", nobody will care. It's precisely this sort of irrational double standard to which the article refers.

Case in point: there is a coal power plant located three miles from downtown DC, smack in the heart of a metro area of 5.3 million people. This is an unhealthy thing to be near, yet people live right next to it without any qualms. I would far prefer to have a nuclear plant there than a coal plant, but coal generation is familiar and thus people are not afraid of it.

Yes, in fact, that is my justification. Life is dangerous, but these dangers are not particularly significant. Billions of people live safely in big cities containing scary industrial plants. If people have accepted a small risk as part of their daily lives, but refuse to accept another, smaller risk, then I will call that irrational.

I maintain that your responses indicate that you believe the danger of nuclear power to be far greater than other dangers. You call it "crazy" to build a nuclear power plant in a city. You do not even bring up the idea of these other industrial plants until I did it first. Yet, if they're equally dangerous, having them in cities must be equally crazy. An average city contains hundreds of these things, so surely one additional drop of crazy makes little difference, if it truly is "crazy". Either you're being selective because you think nuclear power is much more dangerous, or you're being selective for no reason at all.

@Dave

I don't think that your analogy is correct. The major high-profile nuclear power accident was far worse than any act of terrorism has been so far. But, unlike terrorism, nuclear power can be made as safe as we want it to be. Western plants have no chance of any accident like that particular high-profile one. They don't even have a significant chance of more minor ones. Radiation leaks from nuclear power plants are, in general, NOT deadly. Take this recent TMI leak for example. The worst exposure was a couple of chest x-rays. The fellow was perfectly fine and will suffer no ill effects from his exposure. That is what a modern "nuclear accident" looks like. Terrorism, on the other hand, actually does kill people and can't be eliminated no matter how much we might want to.

You appear to illustrate the point of that interview quite well. You seem to be unfamiliar with the the actual risks involved with a modern reactor design, and thus fear them.

You assume that all of the (minimum of three) layers of containment would fail. You assume that the exposure would be dangerous. You assume that these risks are greater than other power options. For that matter, you appear to assume that all reactors would be TMI type.

I suggest you do some web searches and learn a little more.Try cross-referencing background radiation levels by state with state cancer rates. You may be surprised. Some researchers believe that humans _need_ a low level of ionizing radiation, just as we need UV exposure to produce vitamin D.

For real fun, plant a dosimeter downwind of a TMI-type plant. Then go downwind of a coal-burning plant and run the same test. Guess where you find the higher readings. Now fly cross-country and take the dosimeter with you. If you fear radiation as much as I suspect you do, that may be your _last_ cross-country flight.

Search on reactor types. There are plans to install a self-moderating reactor in an Alaskan town; it would run for years virtually unattended (in reality, it will be closely monitored, if only to gather data for future production runs). Frankly, I'd like to have a small pebble-bed ractor in the back yard; it would be safer than the big propane tanks I have now. Forget Chernobyl designs; as Michael Ash has pointed out, no one with any sense would try to use that for power production- isn't optimized for that, and the design has inherent flaws.

As for non-radiation risks: Do you prefer steam from cooling towers, or clouds of noxious fumes and mountains of ash? Is it safer to ship tons of nuclear fuel or megatons of coal? Are a pile of fuel rods more explosive than a supertanker loaded with a million cubic feet of LNG? Are more people injured or killed mining coal and pumping oil and natural gas, or by mining uranium ore? Is a building full of spinning centrifuges more dangerous than an oil refinery (hint: Texas City)?

Now let's talk efficiency: Roughly 30% of the electrical power produced in the USA is wasted in line losses; even the best cable has some resistance (not counting superconductors; different issues there). Is it more efficient to put a 3MW power plant a hundreds from nowhere and actually receive just 2MW of power in town, or put the plant near town and get close to 3MW? (This issue is part of why I prefer local power production -- whether coal, gas, solar, wind, or nuclear -- to centralized production.)

Michael from ashes would like to live downwind from some nuke hive, he can move there and do it, if he keeps pythons in the nursery at home, its a familiar python so whats to worry about.
he shills for the worse kind of pollution, the dangerous kind that never quits. it will be in the ocean, in the fish you eat, ashes dosent' want to know about it.
modern nuke plants are sometimes built on tectonic fault lines by these geniuses, and their lobbiests and the congressmen they pay. He wont tell you the truth about aging infrastructure that heat and acids have eroded and left cracked and banjaxed

"There have been countless non-nuclear accidents which killed more people than Chernobyl."

Yes but people are still getting ill from Chernobyl many years later and they still will be getting ill in a thousand years time.

I have no idear nor does anybody else how many people have been effected by Chernobyl.

Yes you can talk about more radiation from a coal plant than a nuke, but when operating properly both represent less of a health risk than eating toast.

The think is toast is only harmfull to you for a relitivly short period of time maybe 24-72 hours. A coal plant will be dangerous (not due to radiation" for maybe 100years after it stops working.

Chernobyl will be dangerous for 10,000 to 100,000 years and the area it effected and still does spreads from Russia to England and Northan Ireland. Some estimates are that it has more than doubled the background radiation level (which puts it on par with radon gas levels).

If several thousand tones of ammonium nitrate did explode (as has happend in europe) then people will repopulate the area quite safely within a couple of years.

Oh by the way Chernobyl happened not because of a normal operating accident it happend because somebody decided to run a dangerous "safety check".

That is people who supposadly knew what they where doing did a dangerous thing and it went bad very very quickly. It effected an unimaganably large area and will continue to do so for many many generations.

As Chernobyl happened by human hand it does not realy matter if it was deliberate or not, nor that the reactor was not of an overly safe design.

The reason for this is that with human action all safety systems can be overridden, and due to the way reactors work they cannot be made unconditionaly safe in that environment.

The risk might be low say once in a thousand years, but if the effect lasts for 10,000years you have a bit of a problem...

To be blunt what ever you do "risk is what you make it" and fudging the "risk figures" is easily done not just by design but because we have not had the technology around for long enough to do anything other than guess.

So it does not matter if you think I'm wrong, or I think you'r wrong, the bottom line is we do not have sufficiently reliable information to tell.

You, too, are doing a great job of illustrating this man's point about the fear of the unfamiliar.

I particularly enjoy your "nobody knows" approach to Chernobyl effects. In reality, the consequences of the Chernobyl accident are quite well known. The quantity and distribution of the radioactive materials spread by the accident are known. The health consequences are pretty well known. It's true that you won't find a listing with five digits of precision showing you exactly how many lives it has cost in the long run, or how many years of life lost, but the people who actually understand and study these things do have a pretty good idea of how many people were affected and how badly they were affected.

I have no idea what risks you think exist in eating toast, but I can guarantee you that living near a coal plant is not safer than eating toast. There are real, dire health consequences that come from living downwind of a coal power plant, which kill people on a daily basis. Particulate pollution is unfriendly. The average coal plant you find today does not scrub its exhaust 100% clean, or even close. (My local one, the one on the Potomac, 3 miles from downtown DC, claim to scrub 98% of pollutants. Considering that they're receiving and burning about a train full of coal every day, that remaining 2% is not comforting.)

However, what really reveals the depth of your ignorance is your statement that Chernobyl's design does not matter because the accident was caused by human stupidity. While you're absolutely right that the proximate cause of the accident was a dangerous experiment, the reactor's design contributed immensely. Properly designed power reactors use a containment dome. This is a huge dome made of six-foot-thick reinforced concrete which covers all the nasty bits of the reactor. A fire such as happened at Chernobyl would be contained within the dome instead of spreading reactor bits over the countryside. Furthermore, the RBMK reactors (many of which are still running in the former USSR, if you want to think about something that's legitimately frightening for a moment) have what's called a positive void coefficient, which basically means that they're inherently unstable and require active control at all times to avoid a runaway reaction like what happened at Chernobyl. Again, properly designed reactors do not have this property.

With a modern, well-designed reactor, a Chernobyl-style accident simply cannot happen. It doesn't matter how stupid or incompetent the operators are, it can't be done. The risk of such an accident with such a design is not low, it's zero. Thus your idea that Chernobyl's bad design ultimately didn't matter is just plain wrong.

And finally you close with another run of the "nobody knows" approach. You can feel free to wallow in your own ignorance, but the fact is that there are plenty of nuclear physicists and engineers who actually do know what they're doing. We know how these things behave, we know how to make them safe, and bringing up Chernobyl over and over again just shows that you don't know what you're talking about.

@Clive
It isn't at all clear that any amount of information would be "sufficiently reliable" to please you. But just as not believing in Newtons laws won't protect you from bullets, your lack of knowledge about nuclear safety engineering doesn't keep people from dying due to coal pollution.

So the problem isn't that cars kill more people than nuke plants. They are somehow different, no?

So how about this. The highest estimates that I can find for the total deaths from Chernobyl are similar to the estimates that I can find for the yearly deaths from air pollution due to fossil fuel based electricity production. We don't have a Chernobyl every decade. In fact, the only way I can possibly imagine having another one it all is for North Korea or Iran or a similar not quite first world country being stupid.

Refusing to replace coal plants with nuke plants in first world countries costs lives. Your ignorance doesn't keep people from dying.

Let's make sure I understand you correctly: Chernobyl was a flawed design, the operators performed a dangerous experiment with it, made mistakes, and people died; therefore nuclear power is bad because the potential risk (of a Chernobyl-style disaster) that doesn't exist with modern designs is too great.

I usually find your comments better thought out than this. Yes, Chernobyl-type reactors are a bad idea. That's why the West doesn't build them anymore. But don't confuse modern nuclear power systems with obsolete systems. Are electric stoves horribly dangerous because cooking over open fires can be dangerous? What we _should_ be doing is going ahead with existing modern technology and get those potential Chernobyls shut down.

And looking optimistically ahead, if LLNL's ICF and LIFE hybrid programs prove out, we'll have a way of dealing with lots of current radioactive waste; instead of sealing it away forever, we would be able to use it.

Isn't the argument about the (rare) risk with a nuclear power plant versus (higher) risks with more well-known forms of industry, similar to the argument about transportation security between air and rail?

Long before terrorism, there were more checks and balances and redundancy introduced by design with air travel. This was for the simple reason that any failure would have catastrophic consequences for the whole flight - the chance of any survivors with a mid-air incident is close to zero. With rail travel, the chance of an incident causing that widespread a loss is far, far less. The more "spectacular" failure gets disproportionately more attention and more concern.

I think you're exactly right. Being anxious to fly once a year yet taking the daily commute in stride is almost exactly the same as being anti-nuke but ignoring all these other industrial processes. The major difference I see is that people who are afraid to fly KNOW that it is irrational, they just can't help themselves. But anti-nuke people almost universally think that their side is the side of reason.

I must disagree about one thing in your post, though. The vast, vast majority of failures on airliners have no consequences to the occupants of the aircraft. Airliners are robust because of redundancy, not because each individual part is incapable of failure. Airlines aren't safe because e.g. the engines never fail, rather they're safe because when one engine goes there's a backup for it. Safe nuclear plants are the same: it's not that they never fail, but that they're designed with incredible redundancy and fallbacks, so that a single failure, or even a drastic combination of failures, does not compromise safety.

I used to live within walking distance of that coal plant near DC. It's just north of Old Town Alexandria and just south of National Airport. Planes fly right past it as they land. Plant seemed very clean.

I also used to live just minutes from the Houston Ship Channel, the largest collection of dangerous refineries and chemical plants in a major US metro area. Warning sirens and disaster drills are a part of growing up there and everyone figures they're mostly safe, and they are. However, they took our F-16's away. Ellington Field is now a minor commuter airport and the home of NASA's "Vomit Comet" and T38 training planes. One hopes that the T-38 pilots would ram any would be attackers.

Major urban areas are hard to evacuate. When Hurricane Rita came so shortly after Katrina Houston descended into madness and meyham on the highways. We shaped up well with better evacuation plans and the Ike evaucation went off without a hitch. But this was mostly because many tens (hundreds?) of thousands of people who left during Rita stayed home for Ike. Ike was a devastating direct hit, but we got through it OK. Death toll was only a little higher than those killed on the road during the Rita nonsense. Ike made us tougher and smarter. We would do well to get hit by an Ike level storm every ten years.

Not to distract from the pro/anti-nuclear-power debate, but isn't "people are more reasonable about familiar dangers" just another way of saying that if people have direct experience with something, they make better decisions about it than they do about things they've only heard about (usually in scary stories)?

Even if the experience is just having it around for 30 years, and nothing untoward happening, that's still experience.

Doesn't that just mean that people are using a good heuristic, which applies only as often as good heuristics typically do (i.e. most of the time)?

You're correct that experience means people can make better decisions. To me, the interesting part is how people always seem to err vastly on the side of caution when something is unfamiliar. I don't see this as being a very good heuristic, personally. It would be as if I treated every person unfamiliar to me as though he were a psychopathic axe-murderer until proven otherwise.

Bruce;
You're not really suggesting Britain is being rational in its response to terrorism, are you? I'm hoping your comment was limited to the Troubles, and not the current-day suspension of due process.
What passes for a rational response to terrorism in Britain today is easily measured against the worst offenses of the USA PATRIOT act.

2, Therefor it requires other systems to function correctly for it to be safe at all times.

3, These systems are usually three or four deep so there is between a 6 - 11% chance of these systems all failing together.

Now at this point you could argue (reasonably correctly) that the system is "safe" in normal operation and I would (within certain limits) agree with you.

Now I'm going to ignore the fact that Chernobyl was a crap design.

But this is the point I was trying to make

5, A human designed a test that removed some or all of the safety features.

6, Another human scheduled the test "by the calender" without checking to see if the state of the reactor was ok.

7, Another human knowing that there where maintanence issues still alowed the test to procead.

The fact Chernobyl is a pile of radioactive slag is not thje dodgy design of the reactor (although it helped significantly), but that "humans disabled the safety systems" and "carried out a dangerous test" for "beurocratic reasons" when "it was known maintanence was in progress".

So the fact it happened is not a technology failure but a deliberate human act.

So does it matter if it was incompetence or terrorism that caused Chernobyl?

No.

And importantly it tells us that humans are the weak link in the safety chain and they are compleatly unpredictable.

So due to humans and their medaling ways I personaly don't think any reactor can be 100% safe unless it is intrinsicaly safe (which it cannot be).

So no matter, what safety systems are in place an idiot can remove them all and the reactor will carry on producing more and more heat until structural integraty is compromised.

And by the way this is not just nukes it's nearly all petro / chemical systems.

The differance is that by and large most chemical messes can be ignored or safely cleaned up within a short period of time.

Saddly a lot of very brave people at Chernobyl gave their health and or life to try to stop the mess the incompetent managers had caused.

6-11%? Seriously? Where did that number come from? I have no idea how you can go from "three or four deep" to 6-11% without any further information about how the system is designed.

There is simply no way for those numbers to make even the remotest amount of sense. It's the logical equivalent of claiming that there's a 50% chance of having a bomb on a plane, because either you have a bomb or you don't, it's 50/50.

If this is the sort of illogical reasoning you're going to continue bringing to the party, I can't see any reason to continue the discussion.

I think NE Patriot has it spot on. When terrorism was a British - not English - problem, the response was fairly rational. People took reasonable precautions. For example, unattended parcels were destroyed. The dangers and the precautions were, at least to some extent, proportionate.

But today, the UK has become badly infected by the US approach to terrorism, which seems to be to create the maximum amount of inconvenience, for the least amount of effect. You could call it the Potemkin approach - the appearance or display of precaution without the reality.

This doesn't surprise anyone in the UK, I suspect. For a century we have had the bad habit of picking up the worst American ideas and pushing them to their limit.

That said, we ought to have known better than to follow blindly in the American path.

Familiarity also breeds complacency. While unfamiliarity can contribute to unnecessary fear, the opposite is also true: people who are overly familiar with something can easily overlook or downplay real dangers. I'm not saying that's the case with nuclear power, as I'm all for increased use of it, but you have to be careful about over-generalization.

"Refusing to replace coal plants with nuke plants in first world countries costs lives. Your ignorance doesn't keep people from dying."

With regard to ignorance I would suggest you stop and consider what you have said, and the false assumptions you have made in just thjose two sentances...

1, At no point have I said that coal fired power stations or air polution do not kill people or make them ill.

2, Nuke's are the only replacment for coal.

I seriously suggest you actually go away and think about what you have said.

The last time I reviewed the "pro nuke" arguments they where all seriously flawed in one way or another and none of the arguments held water, except when seen from a very politicaly skewed and decidedly suspect industry view point.

The first major and seriouisly flawed argument is that "we must consume non renewable resources for energy production"

Nearly all energy sources on this planet are as a result of EM radiation from the sun and as such are renewable. Nukes on the other hand destroy resources that currently cannot be replaced.

The amount of EM radiation energy that can be fairly easily recovered is many many times the projected usage if the world population doubled and all had first world energy consumption at the current levels.

The second is "energy needs will rise as usage rises and thus additional capacity has to be built".

This argument has been more than successfully debunked it is currently used by amongst others EDF. Who find it more benifficial to subsidise low energy lighting than to invest in increased production capacity.

Improvments of just one or two percent in efficiency in the most energy consuminmg equipment used in "first world" countries will negate the need for increased capacity entirely.

A case has been made that the significant energy cost of aluminium and other metal recovery from ore could be reduced to less than 1/10th of it's current requirments with improved recycling and better engineered end products (for instance go and look up the energy requirments to turn iron ore into steel for car production various studies show that it is between 3 and 12 times the energy the car will use during it's life time, further various studies have shown that the quantity of metal used can be easily reduced by significantly more than 50% whilst actually improving car safety...).

Speaking of recycling, the "dirty man of europe" the old East Germany used to recycle around 90% of it's refuse. The only reason it was considered "dirty" was the use of soft brown coal as a primary energy source (and where people are aware of it polution of waterways but other European nations had worse records for that which might account for why it is not as well known as it could be ;).

Thirdly "environmentaly friendly energy sources are unpredictable and primary energy output from them cannot be stored in an environmentaly acceptable way".

Again this has been thoroughly debunked and there are very many environmentaly friendly ways of storing energy.

I could go on and on and on but apart from anoying the moderator and other blog readers what would be the point?

"During a period in 1992, from May 27 to July 14, the coal mining industry did not experience any fatal accidents while producing many million tons of coal--a period of rare length in mining history."

Wow, 48 *days* without a fatality. Amazing.

Averaging about 30+ deaths per year; 33 fatalities in 2007.

The mere existence of the coal plant implies miners to supply it. So coal plants are responsible each year for far more deaths than all US nuclear plants combined.

Actually, more people have died in the late Sen. Edward Kennedy's car than in US nuclear power plant *malfunctions*.

(Source of the following is Wikipedia, but they are well-referenced to reliable original sources.)

"The nuclear industry in the United States has maintained one of the best industrial safety records in the world with respect to all kinds of accidents. For 2008, the industry hit a new low of 0.13 industrial accidents per 200,000 worker-hours. This is improved over 0.24 in 2005, which was still a factor of 14.6 less than the 3.5 number for all manufacturing industries. Private industry has an accident rate of 1.3 per 200,000 worker hours.

"To compare the historical safety record of civilian nuclear energy with the historical record of other forms of electrical generation, Ball, Roberts, and Simpson, the IAEA, and the Paul Scherrer Institut found in separate studies that during the period from 1970 - 1992, there were just 39 on-the-job deaths of nuclear power plant workers, while during the same time period, there were 6,400 on-the-job deaths of coal power plant workers, 1,200 on-the-job deaths of natural gas power plant workers and members of the general public caused by natural gas power plants, and 4,000 deaths of members of the general public caused by hydroelectric power plants. In particular, coal power plants are estimated to kill 24,000 Americans per year, due to lung disease as well as causing 40,000 heart attacks per year in the United States. According to esteemed journal Scientific American, the average coal power plant:

***emits more than 100 times as much radiation per year than a comparatively sized nuclear power plant does***,

in the form of toxic coal waste known as fly ash."
************
Note that to the best of my knowledge, none of the 1.5-per-year-average on-the-job nuke plant deaths were related to catastrophic failure or radiation. If a worker with heart disease has a heart attack in the plant instead of at home, that's an "on-the-job" death. Similarly with the kind of fatal accidents that can happen in any industrial plant, no matter what kind of widgets it produces.

You are being somewhat silly making that claim. The simple answer is that current biologoical effects on the wildlife in the area show little or no relation to what we belived about the effects of radiation (thanklfully they suggest our previous guesstiomates where overly pesamistic).

"In reality, the consequences of the Chernobyl accident are quite well known."

Compleatly false as a statment I do not know where you could possibly have found evidence to back it up.

"The quantity and distribution of the radioactive materials spread by the accident are known."

No they are not known they are estimats at best.

"The health consequences are pretty well known."

Again no most of the assumptions on health consiquences are bassed on the effects of the bombs dropped by the US on Japan and what appear to be overly pessimistic results from very limited experiments.

"It's true that you won't find a listing with five digits of precision showing you exactly how many lives it has cost in the long run, or how many years of life lost, but the people who actually understand and study these things do have a pretty good idea of how many people were affected and how badly they were affected."

I suggest you read that again it is logicaly inconsistant as a statment.

You cannot argue the future unknown against the past unknown.

Also there has been no comprehensive investigation of health in the area covered. So it is an unsuportable statment at best.

"I have no idea what risks you think exist in eating toast"

Simple the parts that go brown or black contain similar micro particulate carcnogens as are found in partialy burning other organicaly produced fuels such as coal or oil. There are however other non organicaly derived carcnogens in coal and oil.

"but I can guarantee you that living near a coal plant is not safer than eating toast"

Stupid statment to make you cann't because we don't yet know what all the health effects are.

"There are real, dire health consequences that come from living downwind of a coal power plant, which kill people on a daily basis."

I'm rather more aware of that than you appear to be.

"Particulate pollution is unfriendly. The average coal plant you find today does not scrub its exhaust 100% clean, or even close."

No but unlike most oil burning engines they atleast try to burn efficiently and then scrub the result.

Have a look around for miocro particulate concentrations for motorists and pedestrians in major first world cities.

"(My local one, the one on the Potomac, 3 miles from downtown DC, claim to scrub 98% of pollutants. Considering that they're receiving and burning about a train full of coal every day, that remaining 2% is not comforting.)"

Err what percentage of the coal that arrives is "pollutants" also what are the poluitants concerned I think they do not include the simple oxides of carbon.

So you are exhibiting the exact same "illustrating this man's point about the fear of the unfamiliar" you accuse me of...

"However, what really reveals the depth of your ignorance is your statement that Chernobyl's design does not matter because the accident was caused by human stupidity. While you're absolutely right that the proximate cause of the accident was a dangerous experiment, the reactor's design contributed immensely."

The design does not matter because no matter how good or bad the simple fact is it was humans who disabled the safety systems not the reactor.

If you take out the safety system in a deisel engine and then run it don't be surprised when it burns out in front of you.

The question then is "Who is at fault for the burnt out engine?" you who take out the safety system and run it? Or the designer who put it in with insufficient protection to stop you?

"Properly designed power reactors use a containment dome."

Logical fault with your argument, if the reactor is "properly designed" then the dome is not required.

You have just acknowledged my point about the design of the reactor in that it is not (nor cannot) be intrinsicaly safe.

"This is a huge dome made of six-foot-thick reinforced concrete which covers all the nasty bits of the reactor."

Again if a reactor was intrinsicaly safe it would not have "nasty bits" that needed covering in "six-foot-thick reinforced concrete.

"A fire such as happened at Chernobyl would be contained within the dome instead of spreading reactor bits over the countryside."

Sorry compleatly not true. Go look up what happens to the likes of water vapour when even moderatly heated inside a fully closed environment (I'll give you a clue PVT).

"Furthermore, the RBMK reactors (many of which are still running in the former USSR, if you want to think about something that's legitimately frightening for a moment) have what's called a positive void coefficient, which basically means that they're inherently unstable and require active control at all times to avoid a runaway reaction like what happened at Chernobyl."

False argument.

Not having something that makes it "inherently unstable" does not make it "intrinsicaly stable".

"Again, properly designed reactors do not have this property."

I would suggest you have a very long think about that statment and then try to find either science or engineering to back it up.

"With a modern, well-designed reactor, a Chernobyl-style accident simply cannot happen. It doesn't matter how stupid or incompetent the operators are, it can't be done."

I'd love to know how you reasond that out.

There is a fairly famous comment about the "works of man" that effectivly states if man can make it, man can unmake (break) it.

"The risk of such an accident with such a design is not low, it's zero."

I was not arguing about the magnituide of the result (which the poor design did contribuite to) just that it happend due to human action, and thus it can happen again.

"And finally you close with another run of the "nobody knows" approach. You can feel free to wallow in your own ignorance"

You are obvioiusly taking a life long wallow your self.

"but the fact is that there are plenty of nuclear physicists and engineers who actually do know what they're doing. We know how these things behave"

What sub set of the human race is "we" or are you claiming to be a nuclear physisist or engineer or both?

In which case would you care to state what your domain expertise is with regards energy supply industries and nukes in particular?

For your information I have designed many systems for both safety and communication used in the energy "supply" industries including some that are used in nukes.

"we know how to make them safe,"

Again who is the "we" and what do you mean by "safe"?

I don't know of any safety engineers or physasists for that matter who would be so bold as to make that unqualified claim.

I would be interested in meeting one who could, not just say they could.

Because I'd ask them to tell me who's going to win the NFL and other major sporting events for the rest of my life, as they can obviously see into the future and I might as well proffit by it.

"and bringing up Chernobyl over and over again just shows that you don't know what you're talking about."

Err no I think it shows that I do know what I'm talking about "The weakest link being the safety system over riding human".

"6-11%? Seriously? Where did that number come from? I have no idea how you can go from "three or four deep" to 6-11%"

It should have been 6-12% (a slip of the finger on the mobile phone keypad) or more correctly 6.25-12.5%.

If you have a system that consists of identical parts you can arange them in a number of ways depending on what you aim to do.

If you put them in parallel you can make an assumption that they will all fail together in only 1 of the 1/2^n modes. Which occurs about n^-2 of the expected fail time for the single device.

Therefore,

1, 1/2 = 50%
2, 1/4 = 25%
3, 1/8 = 12.5%
4, 1/16 = 6.25%

1, 1.0 = 100%
2, 1.4 = 140%
3, 1.7 = 170%
4, 2.0 = 200%

"without any further information about how the system is designed."

Identical devices in parallel is the normal configuration in safety critical control systems.

"There is simply no way for those numbers to make even the remotest amount of sense. It's the logical equivalent of claiming that there's a 50% chance of having a bomb on a plane, because either you have a bomb or you don't, it's 50/50."

As far as I am aware a "chance" is not a "probability". Therefore "bomb on" is one of two states or 50% of the total number of states.

"If this is the sort of illogical reasoning you're going to continue bringing to the party, I can't see any reason to continue the discussion."

"1, At no point have I said that coal fired power stations or air polution do not kill people or make them ill."

Even with a Chernobyl every decade (which isn't going to happen) nukes cause less deaths than fossil fuels. This is a point which you have chosen not to debate. Yet here you are demonizing nukes, not fossil fuels.

In a perfect green world we could all set up bird friendly windmills that provide power all day every day without being eyesores and without requiring expensive maintenance. In practice we have to choose between power options and choose the best based on how they actually work.

"2, Nuke's are the only replacment for coal."

They don't cause bird deaths like large windmills. They don't destroy salmon runs or otherwise cause the environmental catastrophe that is a hydroelectric dam. They aren't dependent on weather or climate. They can be built essentially anywhere, and are cheap per GW/h. The lifetime amortized cost for a GW/h of nuke power is a fraction of cost of running just the scrubber while producing a GW/h of coal power.

It is good for the environment, the economy, and national health to use nuclear power. Nothing else comes close by any rational measure. However, instead of doing the rational thing we have irrational fear mongers harming countries in multiple ways.

As for statistics.. well... counting states is fine, but then you have to be even better at statistics. I mean, there are only two options.. I'll get a blow job from a supermodel tonight or I won't. But that doesn't mean that they are equally likely. If you have 3 things that have each have a 1% chance of failing in a 50 year time frame, the odds of them all failing in 50 years are what? Now assume that they have people monitoring things, willing to shut it down if any one fails. What are the odds of all three failing in, say, the few hours it might take to notice a small leak?

Now honesty makes me mention that things might get slightly worse when we consider correlations of failures and so on. However, an actual statistics course is outside the scope of this post.

@Michael Ash: "To me, the interesting part is how people always seem to err vastly on the side of caution when something is unfamiliar."

Haven't we had this topic here before ? It's simple - what you're familiar with hasn't killed or crippled you (yet), what you're not familiar with, might. So why take chances if you're comfortable with your current situation ?

"It would be as if I treated every person unfamiliar to me as though he were a psychopathic axe-murderer until proven otherwise."

Xenophobia, racism, the concept certainly isn't unknown.

Axe murdering may be a bit out of fashion, so your prior probability of encountering a practitioner of this pastime may be low enough that you wouldn't suspect strangers of this particular vice, but just watch who will be among the first suspects when a chopped-up corpse is found in your village ...

Your 6.25-12.5% argument is hilariously flawed. This is the kind of thing a mathematician might write to another mathematician as part of a joke.

Here in reality, you have to actually know the reliability of the individual parts in order to talk about the reliability of the system.

By way of illustration, let's imagine a 747 with 4 engines. Let's imagine that each engine has a 1% chance of failure due to internal reasons on any given flight. (This number is way higher than the real number, and is purely for purposes of illustration.)

The probability of any given engine failing on a flight is 0.01. The probability of having an engine failure during a flight actually goes UP, and is roughly 4%! However, the probability of having multiple engines fail independently is equal to the probability for each one raised to the fourth power, 0.01^4 = 1.0x10^8 or one in 100 million.

Let me reiterate that: 4% chance of an engine failure, but only 1 in 100 million chance of losing them all, with 4-way redundancy.

Your 6% figure is complete nonsense. I beg you to take an elementary probability or statistics course.

So my one nuke worker dies thats a 100% death rate in that year for the nuke industry "Oh my God Nuke power plants Kill every work in the industry"...

To get the same death rate 10,000,000 coal workers would have to die in a year...

Therefor for the 100% death rate working with nukes is 10,000,000 times safer... But if my one nuke worker does not die then the nuke industry is C/0 times safer which is as close to "infinatly better" as we are going to get ;)

You are immediatly going to say "but you cannot do that as you are not comparing like with like".

Which is the point the raw numbers are meaningless without a great deal of further information.

Which we don't have.

Just to put a pinapple on top of my silly cake,

Of course my solitary nuke worker could have tripped over his own shoe laces walking up to the nuke powerplant entrance and fractured his skull on the door step.

"Oh my god rouge operator destroys nuke industry safety reputation"

As I have said in my post above before all this sillyness,

"To be blunt what ever you do "risk is what you make it" and fudging the "risk figures" is easily done not just by design..."

It's a point many others on this blog page have not picked up on in their "arguments" and "facts".

"nukes cause less deaths than fossil fuels. This is a point which you have chosen not to debate. Yet here you are demonizing nukes, not fossil fuels."

Your assumptions are, flawed.

1, "nukes cause less deaths than fossil fuels"

Maybe true within certain bounds but not in others, you bounds are not stated.

For instance even saying 40,000 died in 2xyz of partialy burt fossil fuels particulate related illness has a number of issues.

1.A, where did the particulates come from?

It could be from a power plant but the amount of powerplant particulate is orders of magnituide less than from all the other burning of fossil fuels.

1.B, Further death from respitory illnesses can be many decades after the cause was breathed in by the individual.

1.C, It is a fact that some people are dying of resptory illness that they effectivly contracted before the nuke industry existed.

1.D, Likewise there are people that have just been exposed to ionising radiation who will not die for many decades, and their death at a particular time may or may not be related to there exposure.

2, "This is a point which you have chosen not to debate."

So what?

2.A, Neither you nor others have presented meaningfull argument about it to debate.

2.B, Further your nuke related argument is equally as void of meaning.

2.C, you have made your statment about me not debating foissil fuel particulate when you have not yet responded meaningfully or at all to points I have raised about your "emotional view point".

3, "Yet here you are demonizing nukes, not fossil fuels."

3.A, No I'm not doing any such thing. All I'm doing is responding to your highly selective critisisum.

3.B, You are the one raising your arms in the air and screaming "demon demon demon"

3.C, Simpley because somebody dares make comment on you factualy unsuported assumptions.

3.D, Likewise your deliberate miss use of selective facts.

I'm sorry but your emotional assertions are not making you look at all rational in your argument.

If you want to argue that your "emotional view point" that "nuke=good any other energy source=bad" you had better come up with some reliable argument not highly selective half truths.

I will read any further posts you care to make, but I will only respond to those that contain meaningfull facts germaine to this blog page as I realy do not wish to cause the Moderator to raise the "off topic red flag".

my mom worried a lot, I know because she was always telling us about it. My girlfriend was named hope, another point of view on what we cannot know.
Risk is a value judgement, change and physics is a certainty that we do not know how to predict and ultimatly never will.
regardless the dangers some may have all around them, security is only a warm feeling, like anger and other feelings, it will come and go.

The underlying point Bruce is making is correct. We need to take direct action to reduce the level of fear of Americans. Unfortunately we can no only claim to be the land of the free and the home of the brave. The blessings God has bestowed on America, media reporting of disruptive events and a constant search for opportunity to expand the scope of government has made us as a people fearful and gullible.

I don't think Bruce is actually advocating putting nuclear plants in the middle of large population centers. I think his comments are simply a pedagogical device. made to get people to think. I think he accomplished his objective.

"You are immediatly going to say "but you cannot do that as you are not comparing like with like".

Please don't tell me what I'm going to say. Ask your question or make your point, then let me answer or refute it. Projecting weak arguments onto your opponent, then defeating those weak arguments, is commonly known in formal logic (did you ever take that course?) as the "Straw Man" argument, and logicians consider it totally invalid.

"But it does not say what the ratio of Nuke to Coal popwerplants is, nore does it say what the ratio of workers is."

Yes, it does. You either didn't read that part, or chose not to read what doesn't fit your preconceptions, so here it is again.

"For 2008, the industry hit a new low of 0.13 industrial accidents per 200,000 WORKER-HOURS. This is improved over 0.24 in 2005, which was still a factor of 14.6 less than the 3.5 number for all manufacturing industries. Private industry has an accident rate of 1.3 per 200,000 WORKER HOURS."

(capitalization mine, as lower-case apparently doesn't register well with Clive)

"Which is the point the raw numbers are meaningless without a great deal of further information. Which we don't have."

Yes, we do. See above.

Worker-hours adjusts the statistics very well for "what the ratio of Nuke to Coal popwerplants is, nore does it say what the ratio of workers is." Worker-hours did that for you. You chose to ignore it.

In fact, your argument strengthens the case for nuke even more. If indeed one nuke plant worker replaces ten million coal plant workers (your assumption), then the 14-fold increase in worker safety as compared to *all* industrial plants becomes a 140-million-fold increase in safety in terms of worker-hours. I realize you were exaggerating (I think) the ratio to make your "point", but whatever the actual numbers are, you're still arguing in favor of a less labor-intensive industry vs. a more labor-intensive, especially when the accident rate per WORKER-HOUR is *lower* in the less-labor-intensive one.

And you've conveniently chosen to ignore the coal-mining-deaths issue. AND the 100-fold increase in radiation from a coal vs. nuke plant. I did my best by highlighting it for you in my OP, but here it is again:

"According to esteemed journal Scientific American, the average coal power plant:
emits more than 100 times as much radiation per year than a comparatively sized nuclear power plant does, in the form of toxic coal waste known as fly ash."

Got an answer for that one?
*****************
"Sorry what is illogical about normalising the number of states?"

Others have demolished the ridiculous "50%" failure-rate assumption, but one more: Any given lottery ticket can either win the jackpot, or not. So there's a 50% chance of my ticket winning. Which means that on the average, half of all ticket buyers would win the jackpot. Do you observe this happening?

And if I buy ten tickets, then the chance of at least one of them winning becomes 1023/1024 = p = 0.9990234375, or 99.9+ percent. Why aren't we all rich (and the lottery bankrupt?)

Take a course in math, in probability and statistics, in formal logic, and probably in remedial reading, before you continue to post here; otherwise, I think we're all trying to teach a pig to sing. (Isaac Asimov said not to do that. It wastes your time and annoys the pig. He's right on both counts here.)

*****************
Moving on to a more rational topic: (Disclaimer: *I am not a nuclear engineer*), IIRC, there's another difference between Chernobyl and US plants that I don't think anyone here hit directly. I can't immediately source the quote, but it might have been Bruce himself. Namely, that the Chernobyl plant was designed to "fail-dangerous", whereas US plants are designed to "fail-safe". In shorter terms (in case Clive is still with me), at the Chernobyl plant, any cooling failure or increase of reactor temperature *sped up* the reaction, thus creating more heat, which sped up the reaction even more... a "vicious cycle" that ends in catastrophe. Properly designed US plants, IIUC, are designed so that in events like the above, multiple automatic mechanisms *slow* the reaction, or even halt it. Big difference.

If there is a nuclear engineer or other expert in this field present, I would appreciate either being backed up or corrected, since I can't immediately source it. But if true, it would certainly explain why even the US's worst incident, TMI, did minuscule harm compared to Chernobyl.

Yet another factor was the value of human life to the Soviet Union -- zero. To prove that Chernobyl wasn't the only example of sacrificing safety to cost, see the docu-drama "K-19: Doomsday Submarine", about a cooling failure/reactor overheat aboard the Soviets' first nuclear-powered nuclear missile submarine. It had no pressure gauge on the cooling system, and lacked the multiple-containment structures of US nuclear-powered subs, and so the crew could not repair the cooling system without being exposed to deadly radiation.

Finally -- and I'm no longer addressing the deaf and blind here, but those who understand the point of Bruce's post -- consider the St. Lucie Nuclear Power Plant, owned and operated by a stockholder-owned utility, Florida Power and Light. It's on Hutchinson Island, near the city of Fort Pierce.

I've visited the area several times. It was a bit surprising to see megaphone/sirens/horns/whatever attached to power poles throughout the area, undoubtedly at the demand of the type of fear-mongers who are the target of this post. Signs by the horns specifically state that they are for the event of a severe nuclear incident. Yet the residents seem hardly to notice them. Their "familiarity" (I think that word is in the article Bruce cites) causes residents to ignore their presence, just as postulated in the blog article, unless they go off. In 33 years, they haven't, and the plants' operating licenses have been extended by the US Nuclear Regulatory commission to 2036 and 2043. So there's real-world, not theoretical, proof that making something familiar reduces irrational fear.

Three-fourths of the St. Lucie Plant property remain in its natural state of

* mangroves
* beaches and
* swamps.

There are about 180 species of birds and animals that inhabit the St. Lucie Plant property in our wildlife preserve. Of these, 36 are endangered or threatened.

Sea turtles return annually to nest on isolated plant beaches."

I'd like to see a coal-fired plant make those claims.

Oh, and by the way, the late Senator Kennedy blocked the construction of power-generating windmills *five miles* (~8km) from his beachfront home on Cape Cod, because they might "ruin the view". Accurate renderings showed that they would have been barely visible from the beach on a very clear (not foggy) day. Perhaps with binoculars or a telescope...

The heat generated by responders in this thread could replace a large power plant!

Of course, the post wasn't about the wisdom of siting nuclear generating stations in population centers.

Probably, we can all agree that if the V. I. Lenin Nuclear Power Station had been built in downtown Kyiv, rather than more than 100 km distant, it is plausible that a lot more people would have died.

Perhaps we can also agree that while the probability of a large radiation release incident at a Western nuclear station is rather low, this probability is non-zero and of uncertain magnitude - and that the consequences could be very severe.

So the siting of such stations (and many other kinds of facilities that handle very hazardous materials) away from population centers is a sensible policy.

It is also worth considering, that malicious interference could bring about a large radiation release despite the engineering safeguards. If you are skeptical about this, you may find it interesting (as a single example) to investigate what proportion of the mass of extremely dangerous isotopes at a typical Western nuclear generating station is located OUTSIDE the containment.

Stepping back to look at the big picture, I want to argue a bit with the psychologist in the post: people seem to OVERestimate risks of infrequent events when the source is unfamiliar/remote, and UNDERestimate risks of infrequent events when the source is familiar/proximate, especially when the costs of the infrequent event are very severe. Either way, people have a distorted view of reality. Is it sensible to endorse the deliberate distortion of a low-probability risk whose potential costs are so vast?
___________________________________

BTW, in my opinion, there is a myth concerning nuclear power in the USA: that the complete stoppage of nuclear generating station construction was "caused" by fears about safety. A nuclear generating station costs many billions of dollars. In the Three Mile Island incident, the power generation industry saw a relatively minor series of failures and mistakes wipe out a multi-billion dollar asset in a matter of hours.

Think about this for a minute: even those who are sure that a public safety accident is very unlikely, will likely concede that the probability of safely contained plant-destroying accidents is very much greater. I know of no other type of industrial facility where such a valuable hard asset can be destroyed so quickly, easily, completely, and irreparably.

This characteristic makes investors and managers nervous. In the USA, we have no problem throwing thousands of human lives away (I can cite numerous examples), but when piles of money are threatened, the powerful can spring quickly into action!

Of course, this financial risk problem can be practically solved by a scheme of insurance, provided that the probabilities can be estimated in a way that satisfies not public safety advocates, but MBAs.

IMO it's disingenuous to claim that the lack of new nuclear generation capacity in the US is due to financial reasons, not safety worries. Excessive safety regulation is the reason that new nuke plants aren't profitable to build.

There exist reactor designs which are essentially immune to catastrophic failure, even of the non-fatal kind that TMI experienced. They aren't being built because the political climate essentially doesn't permit it, not because the risk of a financially expensive accident is too great.

for a thorough evaluation of fear vs the WORST nuclear accident the world has ever seen, Chernobyl read on : http://www.michaelcrichton.net/speech-complexity.html - seriously, it's worth considering how seriously bad radiation can be (Chernobyl by the way, was still in operation for 14 years after the accident)

@furnace51: What does it mean to say that Chernobyl was the WORST nuclear disaster the world has seen? (In the field of safety engineering, the word "accident" is avoided - everything happens for a reason, so safety incidents are not accidents at all.) In the history of civil nuclear power generation, it is the ONLY disaster. So I can equally say that it is the SMALLEST disaster in the history of civil nuclear power generation. Do you believe that it represents the worst plausible scenario? Based on what analysis?

It is widely accepted that numerous cancers among children are due to contamination from Chernobyl. The best estimate today is that 4000 excess cancer deaths can be expected. It is perhaps the second most deadly industrial disaster yet recorded, and among industrialized countries, the most deadly.

If the Lenin Station had not been sited as far as it was from population centers, or if the winds during the time of the fire had been blowing northerly to northwesterly (as they do there about 12% of the time), the totals deaths could have been many times greater.

Furthermore, probably less than 5% of the core material was scattered any significant distance from the reactor building. While this is an enormous amount, it is not clear that a nuclear reactor failure could not significantly exceed this.

My point is, this was a quite severe as industrial disasters go, and it could have been much, much worse.

By the way, I am not an 'anti-nuclear' guy. I believe that a strong public policy case can be made in favor of electric generation by fission plants. Distinct from whether this type of generation is a good idea, is the question, does this technology pose acute risks that are different from other technologies? Letting advocacy drift into distortion of reality, actually undercuts the advocate's argument.

@Michael Ash, moo:
I am well aware that there are reactor designs that are more stable than those most commonly constructed - I have studied this technology for decades, though my information is now dated. As far as I know, all of these alternative designs have substantial cost penalties that impact the economic equation.

If it doesn't work as a business proposition, corporations won't want to build it.

My point is simply that the economics of reactors are inextricably linked to safety regulations. Not only the vast over-regulation of the nuclear industry, but also the under-regulation of others. Safe reactor designs are still harmed by the insane regulatory environment. As long as nuclear suffers from an adversarial regulatory environment, and alternatives like coal get a free pass from the government to externalize many of their costs onto the public, you can't really say that the nuclear option is bad for purely economic reasons.

@Clive Robinson

Your math "proves" that every time one of my headlights burns out, there is a 50% chance that the other one burns out too. It "proves" that if I drop my phone and destroy it, there is a 50% chance that my wife's phone will also have been put out of operation somehow. I don't need to have designed multiply redundant hardware systems to see that this is 100% pure Grade A nonsense.

Tell you what: how about you tell us what multiply redundant hardware systems you've designed, so I can stay far, far away from any of them.

Hmmm - sounds like a *very* good reason to replace 10,000 coal plants with one nuclear plant."

Ahh I see you either did not read my post properly or you misunderstood the preceading part to that you quote.

Sorry I'll try to remember thjat you need sarcasam quotes. But I would have thought my comment about 'putting a pinapple on the silly cake' would have given you a clue if you had read it.

" "But it does not say what the ratio of Nuke to Coal popwerplants is, nore does it say what the ratio of workers is."

Yes, it does."

No it does not go back and read your own post.

"You either didn't read that part, or chose not to read what doesn't fit your preconceptions, so here it is again.

"For 2008, the industry hit a new low of 0.13 industrial accidents per 200,000 WORKER-HOURS. This is improved over 0.24 in 2005, which was still a factor of 14.6 less than the 3.5 number for all manufacturing industries. Private industry has an accident rate of 1.3 per 200,000 WORKER HOURS."

As I said it does not mention the ratios, so thank you for confirming that you had not read what I had writen...

By the way "WORKER HOURS" is not valid unless all the jobs are identical and in the same proportions in both coal and nuke.

I'm surprised that such a statistical expert as you claim to be would not know that. So I'd better explain,

As a lot of people know the easy way to make a false point is to select a statistic that best fits your view point and make it look like you are comparing like with like when you are actually not. Further to selectivly pick the statistic that is only marginaly germain to the original argument.

Politicians do this all the time so I should ask when we are going to see your real (not gost writer) name on a ballot paper.

" In fact, your argument strengthens the case for nuke even more. If indeed one nuke plant worker replaces ten million coal plant workers (your assumption), then the 14-fold increase in worker safety as compared to *all* industrial plants becomes a 140-million-fold increase in safety in terms of worker-hours. I realize you were exaggerating (I think) the ratio to make your "point", "

No I was making a silly argument to prove a point about silly arguments but I guess you misunderstood.

"but whatever the actual numbers are, you're still arguing in favor of a less labor-intensive industry vs. a more labor-intensive, especially when the accident rate per WORKER-HOUR is *lower* in the less-labor-intensive one."

Ah ha, then you do know that your "worker-hour" argument is not comparing like with like, so it is not relevant without further information that neither you nor the person you quote supplied.

"And you've conveniently chosen to ignore the coal-mining-deaths issue. AND the 100-fold increase in radiation from a coal vs. nuke plant."

Why should I?

I did not raise the issue of coal -v- nuke, why you and others think I did is beyond me.

I hate the current coal power station industry and would wish to see it replaced. It is probably the least environmentaly friendly in the power generation industry there is.

And by the way it's not just miners it's all the others that are involved directly or indirectly like the miners families the transport workers and their families etc etc etc.

With regards to,

"According to esteemed journal Scientific American, the average coal power plant:
emits more than 100 times as much radiation per year than a comparatively sized nuclear power plant does, in the form of toxic coal waste known as fly ash."

Go back and read what I said about toast and why.

I'm very well aware of what toxic chemicals come out of fossil fuel usage and what radioactive contaminats are in our urban environment.

For instance are you aware of Radon Gas in homes and how it gets there?

Likewise which building materials have significantly measurable levels of radiation?

With regards my statment,

"Sorry what is illogical about normalising the number of states?"

It is a usefull way of comparing various safety systems during the design process. If you want to know more I will quite happily email it to you.

"Others have demolished the ridiculous "50%" failure-rate assumption"

Sorry it's "failure states" not rates, you must have made an incorect assumption as have others.

"Any given lottery ticket can either win the jackpot, or not. So there's a 50% chance of my ticket winning."

Compleatly false. It has two states "it won" "it lost". "It won" is 50% of the possible states not the probability of the states.

"Which means that on the average, half of all ticket buyers would win the jackpot. Do you observe this happening?"

No because 99.99..% of the tickets are in the "it lost" state only one is in the "it won" state.

"And if I buy ten tickets, then the chance of at least one of them winning becomes 1023/1024 = p = 0.9990234375, or 99.9+ percent.

Nope, of your ten tickets only one could be in the "it won" state. But the probability of any of them being the one ticket in the "it won" state is very very small (it's lottery dependent).

"Why aren't we all rich (and the lottery bankrupt?)"

Because only one ticket can be in the "it won" state, all the others are in the "it lost" state.

In a single draw lottery each ticket has "one and only one chance" in the draw, what the probability of it being drawn is lottery dependant. After the draw the ticket is either in the "it won" state or "it lost" state the "chance" and final "state" are not probabilities. They can have probabilities asigned to them as atributes.

"Take a course in math, in probability and statistics, in formal logic, and probably in remedial reading, before you continue to post here; otherwise, I think we're all trying to teach a pig to sing. (Isaac Asimov said not to do that. It wastes your time and annoys the pig. He's right on both counts here.)

Funny you sound like you are squealing not singing.

"Moving on to a more rational topic: (Disclaimer: *I am not a nuclear engineer*), IIRC, there's another difference between Chernobyl and US plants that I don't think anyone here hit directly. I can't immediately source the quote, but it might have been Bruce himself. Namely, that the Chernobyl plant was designed to "fail-dangerous", whereas US plants are designed to "fail-safe".

No I think you will find that it was not designed to "fail safe" when the control systems where removed by the operators.

To say something is not "fail safe" is not an argument that it was designed to "fail dangerous".

All systems can have many modes of failure. Some "intrinsicaly" fail safe, most don't. If there is a requirment for it to fail safe and it is not intrinsicaly safe under all failure states then there are two options change the fundemental design or add safety systems to ensure that each failuire state is safe.

"In shorter terms (in case Clive is still with me), at the Chernobyl plant, any cooling failure or increase of reactor temperature *sped up* the reaction, thus creating more heat, which sped up the reaction even more... a "vicious cycle" that ends in catastrophe. Properly designed US plants, IIUC, are designed so that in events like the above, multiple automatic mechanisms *slow* the reaction, or even halt it. Big difference."

No this is the problem people don't appear to understand.

As far as I am aware all nuke reactors currently in use for power generation will enter the run away state if their safety systems are removed and no manual intervention is used. That is the basic designs are all intrinsicaly unsafe to some extent otherwise they would not release energy in usable amounts.

I belive there are designs around for reactor systems that are intrinsicaly safe, but I am not aware of any having been actually built for comercial use.

Depending on who you belive and I have an open mind on it. What caused the Chernobyl disaster was that a safety test that involved simulating the failure of the safety system was carried out on a reactor that was undergoing maintanance work on other parts of the safety systems. The result was the core went into run away and by the time the operators realised what was wrong it was to late to do anything about it.

It is why I say it does not matter about if Chernobyl was caused by the operators or terrorists. All the safety systems where deliberatly removed and by the time the operators realised what was wrong it was to late.

The fact that the basic design of Chernobyl's reactor lacked other safety devices or instrumentation was unfortunate. The sad fact is the plant design around the reactor made the result as bad as it was, but the cause was humans overiding the all the safety systems.

If you take the designs for reactors currently in the comercial sector you can see ways that the safety features can be disabled, they need to be for safety reasons (belive it or not) during maintanence.

Thus any reactor that is not intrinsicaly safe will on having all it's safety systems removed while operating will "melt down" in one form or another.

And it's this "one form or another" that dictates the scale of the effect.

"But if true, it would certainly explain why even the US's worst incident, TMI, did minuscule harm compared to Chernobyl."

Saddly no in all other incidents I'm aware of some or all of the safety systems where functioning and thus the reactor could be brought under control.

"Yet another factor was the value of human life to the Soviet Union -- zero. To prove that Chernobyl wasn't the only example of sacrificing safety to cost, see the docu-drama "K-19: Doomsday Submarine", about a cooling failure/reactor overheat aboard the Soviets' first nuclear-powered nuclear missile submarine. It had no pressure gauge on the cooling system, and lacked the multiple-containment structures of US nuclear-powered subs, and so the crew could not repair the cooling system without being exposed to deadly radiation."

The problems the CCCP/USSR had are complex. The "disregard" for human life is not peculiar to them. Have a hunt around for US and UK nuke bomb tests and what the respective countries service men where ordered to do.

"Finally -- and I'm no longer addressing the deaf and blind here"

That is a very insulting statment to many people and I think you know that you should not have made it. If you where to make it in a large number of US work places you would be looking for new employment. In the UK you could face criminal charges for making it.

"but those who understand the point of Bruce's post"

I certainly do and I was not the one who started side tracking it into other areas.

"consider the St. Lucie Nuclear Power Plant, owned and operated by a stockholder-owned utility, Florida Power and Light. It's on Hutchinson Island, near the city of Fort Pierce.

I've visited the area several times. It was a bit surprising to see megaphone/sirens/horns/whatever attached to power poles throughout the area, undoubtedly at the demand of the type of fear-mongers who are the target of this post. Signs by the horns specifically state that they are for the event of a severe nuclear incident. Yet the residents seem hardly to notice them. Their "familiarity" (I think that word is in the article Bruce cites) causes residents to ignore their presence, just as postulated in the blog article, unless they go off. In 33 years, they haven't, and the plants' operating licenses have been extended by the US Nuclear Regulatory commission to 2036 and 2043. So there's real-world, not theoretical, proof that making something familiar reduces irrational fear."

Yes and the same can be seen around industrial plants etc etc etc. Familiarity breads contempt is another way of putting it.

People don't want industrial plant built near where they live. But once it's built they majority will go and work for the wages the plant offers.

The UK has had many quite serious industrial accidents, one petro plant exploded near London early one morning not so long ago and it was heard by people over 30 miles away (myself being one of them). It was just luck it exploded when it did otherwise judging by the damage to surrounding industrial buildings there would have been significant casualties.

The plant had been there for some considerable period of time and the complaint where few. However there is now an active campaign to get rid of it entirely.

Some people regard the explosion as a wake up call. One person actualy made a comment about "sleepwalking into danger".

"Slightly O/T, but might as well mention environmental benefits:
...

... I'd like to see a coal-fired plant make those claims."

If you can find one built in a similar area at about the same time as this plant it may well do so.

In the UK there are some coal fired power stations that have "wetland" nature reserves or semi wild parkland and nature reserves around them.

Yes coal can be a dirty fuel but so are other fossil fuels. There are other worse industries look at the environmental damage caused by the iron and steel industry for example.

As I have said I don't like the coal fired powerplants and I would like to see them replaced.

But people saying "coal or nuke" is as I have pointed out very very silly.

People should look at all alternatives fully not just partialy.

"Oh, and by the way, the late Senator Kennedy blocked the construction of power-generating windmills *five miles* (~8km) from his beachfront home on Cape Cod, because they might "ruin the view". Accurate renderings showed that they would have been barely visible from the beach on a very clear (not foggy) day. Perhaps with binoculars or a telescope...

Hypocrite.
"
I know very little about the late Senator Kennedy, but his attitude to the "new and unknown" is fairly standard where ever you go.

Personaly I'm not that keen on "windmill" type wind generators, I don't mind the look (but then I find industrial design of interest). They work but the construction costs and reliability info don't give me a "warm tickly fealing" the data they are bassed on is both spars and misleading due to "hidden subsidy" etc.

"Ho hum, lunch time."

I hope yours was not brought to your hospital bed like mine was... Over cooked green veg and tastless meat pie 8(

In the words of Frank Herbert's DUNE, I must not fear.
Fear is the mind-killer.
Fear is the little-death that brings total obliteration.
I will face my fear.
I will permit it to pass over me and through me.
And when it has gone past I will turn the inner eye to see its path.
Where the fear has gone there will be nothing.
Only I will remain.
-- Bene Gesserit litany against fear

I have to say that I feel deeply suspicious of the technique that many people countering Clive's assertions are using: i.e. positing speciously equivalent analogies to illustrate what they perceive to be faults in Clive's logic.

If you make an analogy you must carefully explain the equivalence of every analysable or measurable property of your analogy with every analysable or measurable property of the original system being discussed — or at least explain why it is OK to ignore such a property of the latter. How can modelling the failure of a household's multiple mobile phones be equivalent to multiple failures of safety systems in any nuclear power plant?

This is a general problem with making analogies when it is done to try to simplify something to make it easier to understand. The simplifications often break the intended (analogousness" of the analogy, most always making its usefulness nugatory. I don't claim to understand the modelling techniques that Clive is using to make his assertions, but I know that if your gut reaction to them is incredulity then attempting to rely on your knowledge of O-Level probability to justify your incredulity is likely to be self-deception. If you read something you don't understand or believe, then it is not wise to start out by thinking the reason you don't understand it is because you obviously know better than the author of what you didn't understand. A more constructive course of action might be to try to understand why you didn't at first understand it. If you learn something new from this you might be inspired, and certainly you are likely to be in a better position to make a sound judgment on what you originally read. (And then there would probably be fewer blog entries as precious and patently superfluous as this one.)

"I have to say that I feel deeply suspicious of the technique that many people countering Clive's assertions are using"

You'ld be correct in your suspicions.

"I don't claim to understand the modelling techniques that Clive is using to make his assertions, but I know that if your gut reaction to them is incredulity then attempting to rely on your knowledge of O-Level probability to justify your incredulity is likely to be self-deception."

You are correct.

Both Michael Ash and Ted Kennedy's Ghost are making several mistakes.

The first is neither of them appear to understand how the bell curve is arrived at.

Let's take Michael Ash's statment,

"Let me reiterate that: 4% chance of an engine
failure, but only 1 in 100 million chance of losing them all, with 4-way redundancy."

Whilst he is using (simple) mathmatics to arive at his 4% figure by adding the probabilities which is aproximatly OK when doing "yard stick" measures. He is using the wrong simple maths n^X for his 100 million.

It would be correct for a throw of the dice but not for things like the hight of growing plants all planted at the same time.

That is his 100 million is correct for all four engines stoping at exactly the same infinatly small instant in time and nothing else. Which from an engineering prospective is a compleate nonsense.

Most people after even a moments thought would realise this. After all when a chain breaks which is going to happen one link break or all links break?

There would be a 0.01 probability of one link breaking and 100million of 4 links breaking at the same instant. But you know instinctivly that this is not going happen (hence sometimes gut reactions are correct).

Now look at a simple science project where the students are measuring the growth rate of peas.

They plant them at the same time and the experiment starts.

Each time you look each pea can be in only one of two states, "growing" and "not growing" what the probability is of each state is for each pea is immaterial with regards the overal experiment on growth.

After a week you measure the hight of all the "growing" pea plants and you will find that the hights will fall on the bell curve. This will continue untill all the plants have moved from the "growing" state to the "non growing" state.

The probability of them all dying at exactly the same point in time (without external cause) is so small you would immediatly assume an external unidentifid cause.

Now an important point if you include all the peas in your measurment each time irrespective of what state they are in you will find a seriously skewed bell curve ;)

Now the $64,000 question,

If you performing the experiment in a glass house which has a fully controled environment what curve will you see as the peas switch from "the growing" to "not growing" state with respect to time?

I tell you what let's see what answer Michael Ash gives, and also his argument why his original statment is correct?

Oh Ted Kennedy's Ghost if Michael doesn't have the time to reply maybe you would like to?

Now here is an interesting little thought experiment.

Both Michael Ash and Ted Kennedy's Ghost appear to have a "pro-nuke" and "all other options bad" view point. And have both talked about "coal-v-nuke" as there reason. As many know Coal is assumed to be the worst of the worst for polution, other foissil fuels are better. The various "organic" alternatives can produce as much particulate or more but not the other "real nasties". So they are only comparing against the "worst" not others.

Further their selection of argument and that fact they have not made valid answeres to legitimate questions could be easily taken as either they don't know the answers or they know that they have been caught out making false flag arguments and behaving as straw men. Especialy when they have been so "cock sure" of their opinions they make unfounded, insulting and non germain statments.

Perhaps they would like to argue there behaviour is independent.

Perhaps Bruce would like to look to see if there are "sock pupets" around.

@Clive Robinson:
"As far as I am aware all nuke reactors currently in use for power generation will enter the run away state if their safety systems are removed and no manual intervention is used"

No, that is wrong. Western-style reactors use water as a moderator. When the water is removed, the nuclear chain reaction comes to an end. So even if the cooling system fails and the reactor heats up, the worst thing that will happen is that the remaining cooling water boils, and the reaction coming to an end.

Still, I would not like to be nearby if this happens - the remaining heat would be enough for the reactor to melt down, and the boiling cooling water itself would probably cause considerable damage. But a Chernobyl-like event is not possible.

Clive claims that he can calculate exact probabilities without knowing anything about the systems in question. Quite literally: go look at his post at November 28, 2009 1:37 AM to see what I'm talking about. He claims that these numbers work for any multiply redundant system, regardless of design details, and not limited to nuclear powerplants.

Just read his analysis. Nothing in there limits it to nuke plants. His wording applies just as well to my car's headlights as it does to an RBMK reactor.

"No, that is wrong. Western-style reactors use water as a moderator. When the water is removed, the nuclear chain reaction comes to an end. So even if the cooling system fails and the reactor heats up, the worst thing that will happen is that the remaining cooling water boils, and the reaction coming to an end."

In theory yes...

And that's the problem, I'm an engineer not a theoretical NukePhiz. I know enough to know I don't know enough 8(

So I'm cautious abouit the whole issue.

I have spoken to bothj theoretical and experimental NukePhiz's and asked what to an engineer apper to be fairly simple questions.

The answers you get have two certainties.

The first is wishing you had not asked.

The second is that the answers tend to vary as do the meanings of the terms used (which is always good for a bad requirments spec and acompanying headache ;)

For instance H2O as you say is a moderator like carbon.

Apparently hydrogen has issues as well as impurities carried in the water (steel pipes have increased corrosion and become very brittle the water becomes radio active etc etc).

If the water gets sufficiently hot it turns to steam, if this "vents" to the outside world then there is a risk of it causing problems (again insufficient data to say if it will or not or even what the problems might be 8(

Again there is a difference of opinion of what a "meltdown" is. My simple engineering view point is if it is sufficient to cause warpage or breakage or adversly effect it's operation then it's "melted" beyond design limits.

Others seem to take the view that it is when the core has got to the point radio active materials are "oxidizing vigoursly" (which pulls O2 into the frame).

So you ask the obvious question (is the 02 from the air or the water?) and the answers that come back are not exactly encoraging.

On another asspect which is effects outside of containment. It is a matter of fact that Chernobyl chucked out core material in a way that it was measurable in the UK.

But that is not the issue (unless you'r a sheep farmer in Cumbria) the issue is, is that material dangerous and if so how and over what period of time.

If you hunt around you will find figures of lives effected that vary from as little as 60 to over 30,000 which is not usefull. You also find information about people "chosing to be effected".

You also find information about the wildlife in the area happily carrying on without birth defects etc etc.

In otherwords lots of random data but no real knowledge just a few "questionable" facts...

"Still, I would not like to be nearby if this happens"

You and me both 8)

" - the remaining heat would be enough for the reactor to melt down, and the boiling cooling water itself would probably cause considerable damage. But a Chernobyl-like event is not possible."

Which might or might not be true of current or future reactors in other countries under certain circumstances / assumptions etc etc.

For instance some fifty years ago there was an idea to use carbon sphears with tiny grit like bits of fission materials embedded. Apparantly the system is "inherantly safe" due to "doppler" effects (yes I understand the principle of spectrum broadening but not it's full implications) but hmm it's a nice idea lets see a prototype and stick some measuring equipment around it and see what happens (In the UK in the early days a carbon moderator reactor had problems in that it unexpectadly released an isotope that stopped the reactor).

But please don't do it too close to populations the UK had a carbon moderator reactor (for weapons material production) that was known for problems. You can find small grains of plutonium in the top soil around it for a considerable distance.

Oh and one caught fire taking god knows what up the chimny...

Well in Germany they had one of these carbon sphear reactors running for several years, but shortly after Chernobyl it had some issues and was shutdown.

Now what is not known is the reason, was it,

1, Political
2, Over caution
3, Pragmatisum
4, A real issue.

Some "experts" claim that this carbon sphear system is not "intrinsicaly safe" if you don't...

It's just a mess and a lot of "my guess is better than your guess" from the NukePhiz community.

As an engineer I just whan the theoretical mob to hand it over to the experimental mob and start doing some serious testing in a place it's not likley to cause to many problems should something go wrong (if such a place can be found). That way we might get some answers.

Oh and of course journos don't help, people are afraid of plutonium because they think it's dangerously radio active. What they are not generaly aware of is that on that score you can hold it your hands reasonably safely but it is way more dangerous as a poison...

Both knowledge and Information effect judgment, if either is lacking then the wrong judgment could be made (one way or the other).

One potentially-interesting issue here is that nuke-plant siting and conventional-plant siting. A conventional power plant requires thousands of tons of fuel coming in annually, tens or hundred of tons of waste going out. Produces lots of local unpleasantness. You can only site it in places where there's existing transportation infrastructure (highways, rail lines, waterways), or where new structure can be built cheaply and nondisruptively. Which is why many convential plants have been built on what used to be the outskirts of their urban areas. That's significantly less true of nuke plants.

What you do still have is gigawatts of waste heat. It would be really stupid if you had to earmark 10% or more of a power plant's output to additional air conditioning in the immediate vicinity.

One thing that interests me is how fear (possibly irrational) affects safety measures. For example, people have perhaps an outsized fear of air travel in general--every incident is major news, every fatal incident results in a large-scale investigation and potentially expensive revisions of entire fleets of airplanes. The professionalism and attention to detail involved in inspecting, managing and flying aircraft is way out of proportion to that involved in other forms of transportation, such as driving.

All these safety measures (some more effective than others) add up to a low risk of air travel and therefore an "outsized" perception of its risk. But how safe would air travel be if our fear were "proportionate" to its risk?

Similarly, nuclear reactors are very safe, but in many cases the safeguards and safety measures (including siting reactors out of population concentrations) are extraordinary, and are one of the reasons nuclear power is so safe compared with our perceptions.

Thus, the story of how fear influences our evaluation of risk isn't a simple one: it creates a feedback loop that actually changes the degree of risk.

Y'all are being smidiots, addressing with deep insight and intelligence parts of the elephant but seemingly oblivious the whole animal. Let me attempt not to join you...

1) Fear in some ways is caused by unfamiliarity. It seems that it is also caused by familiarity with a dangerous source (e.g., The more you know a bully, the less you are afraid of her? Not in my experience...). Fear is a natural human mechanism, not to be, um, feared. Let's refactor this conception of "fear is bad" to something like "irrational fear causes more harm than good, and should be mitigated cost-effectively".

2) Familiarity != education. I think what we should be addressing is education, not familiarity.

This is especially true where there is vanishingly low risk but non-trivial cost.

E.g. - They were so familiar with fissile materials at Los Alamos, at least one scientist forgot what could happen if they were mishandled, and died as a result.

==> The flipside of irrational fear is irrational complacency. They both have a cost.

... The good news is that we can educate without increasing the potential cost (in health) one infinitesimal bit.

3) Nothing in life, in my experience, has 0 risk - except, apparently, the 'risk' of not dying.

. It's idiotic to ratchet up the cost of anything without effectively increasing the value.

Conclusion?

Let's keep building nuclear power plants where they could do the least damage, in case of (extremely unlikely, but extremely horrible) catastrophe. Let's make all relevant info available & consumable so that the fear - or, let's call it 'respectful awareness of possible danger' - is the right amount, without incremental but needless increase of potential impact.

Bigger point - let's get together to stamp out smidiocy! (== smart idiocy, == genius in the details, oblivious of the gestalt; "all trees, never quite the forest")

"Many people all over the world have Uranium in their water. Does that mean that water (in general) is dangerous?"

Ah you understand the point 8)

The problem with the "nuke power" debate is a lack of agreed information (facts).

Also the (suppposed) facts are misleading.

The fact that something is in measurable quantities does not mean it is harmful.

But talking about can make it harmfull.

Chernobyl chucked out core material over a very very wide area.

Was it harmfull?

The correct answer is "unkown", as the evidence is not yet here.

Officials erred on the side of caution (why is a matter of opinion).

They issued various instructions that changed peoples lives, most for the worse.

So the answer is "yes people have been harmed by the results of the Chernobyl disaster", but without the supporting information the wrong conclusion is drawn that "The Chernobyl Disaster harmed people".

You can lie by telling the truth...

However even if it was not a deliberate policy to cause harm. It may well have happened that way any way Politicos must be seen to act to "Oh m'god" and they care not who it harms provided it's not them etc etc.

And in general people encorage the "Don't panic, we're doing something" out of the politicos, simply because the lack of hard information encorages the vacum to be filled...

"So no matter, what safety systems are in place an idiot can remove them all and the reactor will carry on producing more and more heat until structural integraty is compromised."

That is not how modern reactor designs work. You would do yourself well to do some minimal research on this topic, which you seem so passionate about.

The failsafe mechanisms in modern nuclear plants are not so much physical devices as they are properties of the device, governed by basic physics.

As a brief layman's example, if you boil off the coolant in a modern reactor (as would happen if the reactor became too hot, or if the containment vessel was breached), the reaction would stop. This is because the coolant plays two roles, cooling the reactor, and slowing the nuetrons emmitted by the fuel. When the neutrons in the reactor are no longer being slowed by the coolant fission grinds to a halt.

The dude in the interview wants to excessively simplify things:
Look at autism or breast cancer- increased prevalence and incedents or personal testimonies from those close to most persons only aggravates the desperation that along with it panic that causes people to seek to protect themselves in irrational ways.

I don't know how one can measure as rational the UK and Israeli reactions to terrorist threats. Rational compared to what. If you went to UK during those terror years all those anti-terror measures would likely creep some folks.

The reactions in Israel and UK are nothing more different than to those in the USA after Sept 11. The people have been willing to forego some freedom in exchange for a feeling they are proteced

The same goes for breast cancer. The cost/benefit analyses in tthe new USA guidelines suggest general recommendations that go against what the general public feel comfortable about. People generally are willing incur costs and disadvantages unnecessarily in because that's the option they fell more protected More harmful screenings and false positives is a price they willingly choose to pay in orderto feel they are doing their best to protect themselves.

Increased cases of breast cancer in people close to someone only agravated the irrationality one can tolerate in order to feel protected

Nuclear Reactors are constantly venting radioactive gases and regularly experience incidents which involve actual or potential release of radioactive products. Previous incidents in the USA have been characterised by an almost total failure to assess the true extent of the incident or its long-term effects.
In addition, there is the production of extremely dangerous fission products for which there is currently no known method of disposal which have been accumulating in ponds and casks for the last 50 years rendering large patches of our environment unfit for human life. Nuclear power plants tend to have a working life of around 40 years, after which they must be decommissioned, but they need to "cool off" for a decade or so before that happens.
None of these costs or risks are paid for by the nuclear industry.
"Safe modern reactor design"? Modern reactor design is focussed on reducing cost. Seeing as the industry bears none of the risk, they ignore it. The key words from a revealing genIV design-reated paper, if I recall correctly were "eliminating systems subject to regulation".
And you want these things in the middle of cities? Talk about abysmal risk management!
Chernobyl will inevitably happen again so long as this ridiculously dangerous and heavily subsidised indutry is allowed to carry on.

Having come late to the game, I'm going to ignore the main flamewar and pick up another point from the quotation:

"If we're serious about health in relationship to nuclear power, we would put them in downtown, big cities, so people would see them all the time."

Chance of dangerous leak from operating power plant = very low.
Chance that in about 30 years you'll have a chunk of land unusable for anything = 100%

One day, your beautiful new power station will become an ugly old power station. While much of it can be demolished, the reactor core and containment will have to remain there for a very long time. This isn't a sensible thing to do to downtown prime real estate (or even suburban real estate.)

""So no matter, what safety systems are in place an idiot can remove them all and the reactor will carry on producing more and more heat until structural integraty is compromised.""

Please note I said "strctral integraty" which means any distortion or break in the core that would prevent it being reused just by filling it up with water again.

I was not talking about being effected a thousand miles away.

Part of the problem with talking about what is and is not safe is the meaning of words (and it can have significant issues, not just to system design but liability).

"That is not how modern reactor designs work."

What do you mean by "modern" the majority of nuke power stations in use are older than graduates. In "modern electronics and computer design" people are talking about "1 generation = 1 year"

So modern has a relative meaning, which you need to consider.

"You would do yourself well to do some minimal research on this topic"

Now there is a very silly statment. "Minimal research" gives you an aproximation to how things work. You go up before a judge and say well I did minimal resarch on the problem and I concluded it was safe".

Minimal research does not work in court and therfore cannot work for safety systems where liability is involved.

"which you seem so passionate about"

Not particularly many people here are making statments such as your,

"The failsafe mechanisms in modern nuclear plants are not so much physical devices as they are properties of the device, governed by basic physics."

It sounds good now go talk to NukePhiz's and aske them to tell you exactly what would happen so you can design the system.

All of a sudden you find there are a lot more problems than just will the reactor stop (which it will).

You have to look at all the failure modes and that is when you find that we realy do not know the answers.

If you don't know the answers then you cannot say something is "unconditionaly safe".

For instance have you ever seen pure uranium metel being handled?

Do you know why it is done in an "inert atmospher"?

Is the answer to be found with "minimal research".

Does it have a bearing on safety issues?

"As a brief layman's example, if you boil off the coolant in a modern reactor (as would happen if the reactor became too hot, or if the containment vessel was breached), the reaction would stop."

Yes but that is just the start of the problem.

"This is because the coolant plays two roles, cooling the reactor, and slowing the nuetrons emmitted by the fuel."

Ok at what peak core temprature does the reactor stop?

How much energy is there to deal with?

And thousands of other enginering questions.

Each one needs to be considered.

For instance do you know what effect hydrogen has on steel?

Also is water the only moderator that might be present?

To give you a "laymans question",

"What happens when an automatic car runs out of gas on a freeway"?

Can you give a difinitive answer that it is unconditionaly safe?

If you are a safety engineer you would know that the answer is not "yes or no" but "it depends..."

All nuke reactors are the same we just do not know if they can be made "unconditionaly safe" let alone "intrinsicaly safe".

Now the $64,000 question,

Does it matter?

The fact that something is neither "intrinsicaly" or "unconditionaly" safe does not per say make it dangerous.

Do we know enough to say what is or is not dangerous and importantly why?

Again the people who you think would be able to give you answers cannot because they don't know.

The assumption after Chernobyl based on the presumed knowledge of the time was a lot of people would die nasty deaths have deformed children etc etc etc.

Guess what studies of the wild life in the area sugests that our presumed knowledge (which was based on the survivors in japan and other very limited studies) is wrong. Importantly we don't know why, or if the lack of effects on animals such as rodents etc applies to humans.

Well tell you what you go do some of your "minimal research" and tell me the number of people effected by Chernobyl to within say one significant digit (don't forget the sheep farmes in the UK).

My argument about nukes is we have insufficient information to take even a pragmatic aproach to nuke power.

So we can only take a cautious aproach. This aproach makes nuke power overly expensive economicaly.

The figures the industry produce have hidden defered costs, and invariably do not compare like with like.

For instance decomisioning costs invariably use transport figures from the construction industry. Ok but forget that for a lot of the materials the costs will be many many times that of moving asbestos waste.

I am neither pro or anti nuke.

What I do know is we cannot deliver unconditional safety when humans are involved, and we do not know if our current designs are intrinsicaly safe. The minimal evidence available says we need more information that can only be obtained by building systems which there has been very very little of for economic and political reasons.

Therefore we have to know a lot more about the dangers involved to reduce the economic cost.

Industry players and Gov advisors issuing reports and comparisons to other energy systems that are inacurate and biased make people suspicious which means more caution and more economic cost. This is a rising spiral of cost.

The fact that some materials may be radio active for ten thousand years or more may not be a real danger or it might, again an unknown. If it is who shoulders the unknown future cost.

That question alone deystroyes any possible economic comparison between nuke and all other energy systems that don't have any (currently known) hidden decomisioning costs, and the materials unlike nuke can be recycled.

The economic cost of not recycling materials such as iron from nuke decomissioning has as far as I'm aware never had an indepth investigation.

It is important because the ratio between recycled iron and ore extraction is rising significantly and the demand for iron is rapidly increasing as well due to development in all nations.

Personaly I think we are more likley to have fusion systems up and running before we have the answers we need to determin the danger or economic effects with any measure of certainty.

But the one thing I do know is we won't get the answers we need from theoretical science.

"Clive claims that he can calculate exact probabilities without knowing anything about the systems in question."

You are making an invalid assumption, and thus making a false claim.

I will say it again,

Chance != probability

You are incorectly assuming it does.

You by 1 ticket you get one chance to win.

If there are 100,000,000 tickets "finaly" sold then the probability of you wining is 1 in 100,000,000.

Do you now understand why this diference is important?

I will put it another way.

When you buy your ticket you know you have one chance at wining the prize for every ticket you buy. YOU DO NOT KNOW THE PROBABILITY unless you bought the last ticket and where told how many had been sold in total.

The fact that you do not know the probability of winning does not stopy making the choice to buy one chance.

Do you now understand why this diference is important?

"Quite literally: go look at his post at November 28, 2009 1:37 AM to see what I'm talking about."

There is no "Quite literally" about it go back and read it again withouit your self imposed assumptions!

Do you now understand why this diference is important?

"He claims that these numbers work for any multiply redundant system, regardless of design details,"

Actualy I don't, I made a statment about failure modes on the presumption that as it is a safety system that the multiple parts are indeed redundant and aranged in a logical manner to maximise safety.

For your information the number of failure states can be worked out prior to a system coming into existance. It is a valuble design tool when discussing varioius designs and trying to compare their strengths and weaknesess (hence it is logical to normalise the information).

You have to do this otherwise you would have to build many "real prototypes" to find thje best design by "known probabilities".

I realy do not know what you do for a living but I can only assume you have a "lets build it and knock out the bugs as we find them" mentality.

That is how an "artist" or "artisan" works not an "engineer" or "scientist". So I can only assume you are one of the former not one of the latter (please correct me if I'm wrong).

Do you now understand why this diference is important?

"and not limited to nuclear powerplants."

The design process is applicable to the design of all systems irespective of what they are. You are making a mathmatical model that is a framework for analysis and further work.

The model accepts that some information is unknown and thus works with other asspects to produce results irespective of the unknown information.

Do you now understand why this diference is important?

"Just read his analysis. Nothing in there limits it to nuke plants. His wording applies just as well to my car's headlights as it does to an RBMK reactor."

Yes it does but you apear to not understand why.

I do not need to know the probability of an event occuring to say how many events there are or what their effects on the system will be.

So again,

A ticket to a lottery (or any other unknown probability system) gives you a "known" quantity to work with when there is no other information available.

That is two layers of safety that have a fixed number of levels each can only be in one of the total number of states at any one time. The effects of those states on the system may be known without having to build the system.

So if one has 10 levels and the other 3 levels the total number of states is known 3x10=30. The resulting system can only be in one of those 30 states at a time. Two of those states are known "fully working" and "fully failed" other states may be the equivalent of each other (ie 4 lots of 1 engine failed on a 747) provided you know or assume that effects on the system (not the probabilities) are the same or equivalent. Which is not the case for the 747 example the aircraft handles differently for each engine failed.

Do you now understand why this diference is important?

If not give up your argument you are lessening you position with each post you make.

I would love to respond to all of this, but I fear our comments would grow to an unweildly length :). I'll try to keep this as concise as possible while addressing the major points.

Firstly, I believe that we have differing ideas of what constitutes "minimal research". To me, it means something in between spending 5 minutes on wikipedia, and majoring in nuclear physics. A few hours on wikipedia, and skillful googleing should be sufficient to clear up most of your questions/concerns. I don't think that either of us are experts in the field, nor should we be expected to be. We are two individuals debating on the internet, not professional lawyers in court.

Secondly, when I say "modern reactors" I am refering to reactors that one would reasonably expect to be built today. Many currently operational reactors would not qualify, but the topic currently being discussed is about building new reactors, not relocating old ones. The reactors that would be possibly built would be so called "Generation 3" or "Generation 4" reactors. The arguably most sane reactor to build would be a pebble bed reactor (generation 4).

On the topic of safety, generation 3 and 4 reactors are designed with inherent safety, and passive safety in mind. Passive safety specifically was what I was refering to in my previous post. The exact mechanisms and parameters of the passive safety mechanisms in modern reactors vary from reactor design, to reactor design so I won't delve to far into the details. In short though I'll address a few minor questions:

"Also is water the only moderator that might be present?"
No, for example pebble bed reactors use pyrolytic graphite as a moderator, and helium gas as a coolant.

"Ok at what peak core temprature does the reactor stop?"
That depends entirely on the design in question.

"How much energy is there to deal with?"
Again, depends on the reactor design. I assume you are driving at "how much energy is going to be released in the event

of a steam explosion", which is a non-issue for reactors that do not use water as a coolant.

As everyone here should know, there is no such thing as absolute security. Similarly there is no such thing as absolute safety. The best we can do is preform a well reasoned, rational cost/benifit analysis. I believe, and I feel that history and science demonstrate, that the potential safety cost of placing nuclear power plants close to major population centers is extremely low, far lower than the general population percieves it.

This all said, I think there are some very good reasons to not place power plants of any kind in cities. First and formost is the fact that they tend to be ugly as sin. ;)

"I would love to respond to all of this, but I fear our comments would grow to an unweildly length :)"

They possibly might but I suspect that your view and my view are not more than a "cig paper" apart.

The problem is "meanings" of ill defined words, and what is and is not a problem.

No I'm not a NukePhiz (nor would I want to be). The problem is most of them are not engineers or take an engineering aproach. Which is a right royal pain when designing control and safety systems for their not so little toys.

For instance as you say the run away process starts the water "boils off" the core stops.

Then what?

The first problem is how much damage has been done to the core by the residual heat energy (which is a lot for a 3MW output powerstation).

If the answer is none then all you need do is go away and have a coffee or two whilst the engineers fix the problem then "fill the kettle with water again" as it where and be back in business.

However it's generaly not the case damage has been done and the structural integraty of the core is suspect. You now have a billion dollar asset that may not be worth it's weight in slurry that is also "to hot to handle".

The pebble bed system is conceptualy quite nice but I've heard one or two refere to it as the "bucket of nuggets" system.

It has a number of issues not least the volume of spent carbon sphears, that it is probably never going to be economic to reprocess (for anything) and the fact the core size is considerably bigger (~3 times in each dimension) for the same power. Which makes other areas of the plant corespondingly larger.

And the question of what happens when a large kinetic 747 object cracks the core open and also breaks open the carbon sphear outer coating and the carbon at very high temprature meets atmospheric oxygen and aviation fuel. It is a bit of an unknown, we know diamonds can burn or dissolve easily in molten iron as do most other forms of carbon. The question is what happens next...

The answers I asure you are many and varied and boil down to "well I think..."

As I said we need to build a few of the brutes surround them with test kit and run a few experiments (which they had been doing in Germany, but stoped shortly after Chernobyl for reasons unknown).

Likewise kicking a few "pebbles" around to see if they crack under the strain would not be a bad idea either.

Theory only takes you so far, then you need to back it up with experiments. And for a whole multitude of reasons we are not doing them and thus do not have answers good or bad (personaly even if bad I think it's good because you can move forward).

The pebble bed system is conceptualy quite nice but I've heard one or two refere to it as the "bucket of nuggets" system.

It has a number of issues not least the volume of spent carbon sphears, that it is probably never going to be economic to reprocess (for anything) and the fact the core size is considerably bigger (~3 times in each dimension) for the same power. Which makes other areas of the plant corespondingly larger.

And the question of what happens when a large kinetic 747 object cracks the core open and also breaks open the carbon sphear outer coating and the carbon at very high temprature meets atmospheric oxygen and aviation fuel. It is a bit of an unknown, we know diamonds can burn or dissolve easily in molten iron as do most other forms of carbon. The question is what happens next...

The answers I asure you are many and varied and boil down to "well I think..."

As I said we need to build a few of the brutes surround them with test kit and run a few experiments (which they had been doing in Germany, but stoped shortly after Chernobyl for reasons unknown).

Likewise kicking a few "pebbles" around to see if they crack under the strain would not be a bad idea either.

Theory only takes you so far, then you need to back it up with experiments. And for a whole multitude of reasons we are not doing them and thus do not have answers good or bad (personaly even if bad I think it's good because you can move forward).